聚靛蓝胭脂红固定过氧化物酶生物传感器的研究

On Hydrogen Peroxidase Biosensor Based on Polyindigo Carmine as Electron Transfer Mediator

采用电化学聚合法制备聚靛蓝胭脂红膜，并通过静电吸附固定辣根过氧化物酶，形成聚靛蓝胭脂红修饰的辣根过氧化物酶电极。聚靛蓝胭脂红在电极与酶分子之间传递电荷，因此，在没有额外的电子媒介体的条件下，通过循环伏安法考察电极的电化学特性。探讨了pH值、温度、工作电位和抗坏血酸等对此生物传感器电催化还原H2O2的影响。此生物传感器制作简单、响应时间短（5s）、选择性好、灵敏度高，对H2O2线性响应范围为5×10^-7～1×10^-2 mol.1^-1。检出限为5×10^-8 mol．1^-1.

A new amperometric hydrogen peroxide biosensor based on indigo carmine as mediator is applied. Polyindigo - carmine （IN） film is applied by electrochemical polymerized, and then horseradish peroxidase is immobilized by electro- static interaction with polymer backbone. Poly （IN） effectively transfers electrons between horseradish peroxidase and glassy carbon electrode. Electrocatalytic reduction of hydrogen peroxide at the biosensor is evaluated with respect to solution of pH, operating potential and influences of ascorbic acid. The biosensor response exhibits the fine selectivity, high sensitivity and a linear dependence on the analyte concentration in the range 5 × 10 ^- 7 - 1 × 10^ - 2mol. 1^-1. Response time is less than 5 seconds while apparent Michaelis constant Km is 2.51.Lmol. L^-1.